A pump drive of the above mentioned kind has been disclosed in the publication ATZ automobile engineering periodical 91 (1989) 9, page 445. The sealing ring, designed as plastic disc, is here pressed or glued in the drilling. As result of manufacturing tolerances, this rigid fastening of the sealing ring to the pump housing could result in the sealing ring having an uneven sealing gap relative to the hollow shaft. In the extreme case, the possibility that the sealing ring touches the hollow shaft in a certain area exists whereby extreme wear occurs. These problems are further intensified by the fact that the sealing ring and the hollow shaft have different coefficients of thermal expansion.